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  <meta charset="UTF-8">
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  <title>1、计算一个数的阶乘位数多少个零</title>
</head>

<body>
  <script>
    let arr = 5
    let sum = 0
    for (let i = 1; i <= arr; i++) {
      for (let x = i; x % 5 == 0; x++) {
        ++sum;
      }
    }

    console.log(sum)
  </script>
</body>

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